Process of uninterruptedly boiling fulminating mercury



J. MEISSNER May 22, 1934.

PROCESS OF UNINTERRUPTEDLY BOILING FULMINATING MERCURY Filed Aug. 25. 1930 m W .c5 www. w he ms mw am Mm Mw @m7 dem rJ. 0.a Jr mi wJ wm, 01m l. 3 1w L a nw/3. QHMS/J M m 1 Ma W N mtl rm u v P m O 1 H 11 .a m a m D" Patented May 22, 1934 UNITED STATES PATENT OFFCE Josef Meissner, Burbach, Germany Application August 25,

1930, serial No. l477,787

In Germany September 25, 1929 2 Claims.

Heretofore fulminating' mercury has beenproduced periodically in charges only during a number of operations. The operations generally comprised the preparation, boiling and washing.

. v5 However the boiling has been the principal operation in the process of production, it having needed a certain time and having been dangerous in view of the poisonous vapours developed thereby. The working-time of a fulminating mercury plant depends solely on the time required by the boiling operation which, for instance if carried out in a common boiling flask yielding 500 grammes per boiling, lasts from 1 to 11/2 hours. As a further example as far as the quantity of the product is concerned it is remarked, that for a production of say Y kilogrammes in 8 hours approximately 8 to 10 boiling asks are necessary, in each of which 4 boiling operations can be Lcompleted within the 8 hours.

This large number of boiling flasks call for a large structure and for a considerable number of workmen. For carrying out the known boilfing processes it has been necessary to convey the iflasks between the individual boiling operations which frequently has been the cause of accidents owing to the flasks being broken or the fulminating merCurylye being spilled in consequence of theinadvertence of the workmen. To sum up the `,drawbacks of the known uninterrupted process are:-

1. Long time needed by the boiling operations carried out in a number of flasks, so that the efficiency of the plant is small.

2. Escape of poisonous vapours, so that the service is dangerous.

3. High costs of erecting boiling houses and considerable costs of the apparatus needed for the boiling and condensation plant.

4. Large number of spare parts in View of the construction of the boiling and condensation apparatus of fragile material.

5. The fragility of the apparatus is the cause of frequent accidents.

6. High costs of service.

According to the modern point of view of carrying out every chemical process in an uninterrupted operation it has been discovered that also in the case of fulminating mercury the particular boiling process can be carried uninterruptedly. An apparatus has been constructed by which it is possible to carry out the complete boiling process in an uninterrupted operation, whereby the solutions of the primary products are supplied into the apparatus in such quantities which exactly correspond to the progress of the boiling operation. The solutions are charged into the top end of the apparatus and immediately on their admission are subjected to the boiling operation and pass through the apparatus within a certain time (which by experiment has needed about 25 minutes) and the finished fulminating mercury together with the mother lye leaves the apparatus at its bottom end.

The warm vapours, developed during the boiling operation, are utilized during their passage through the apparatus for starting and keeping going the boiling operations, and in view thereof the boilingL process is accelerated considerably. Thus as above described the appartus acts in the manner of a heat interchanger with the result 7o of an ideal utilization of the heat of reaction. The vapours developed in the apparatus are sucked o by an exhauster and precipitated in a condenser. The bottom part of the apparatus is constructed in the shape of a cooler, so that the mother lye and the fulminating mercury leave the apparatus in the cooled condition. An air inlet pipe is arranged in the bottom part of the apparatus, in order to promote the cooling action and prevent a vacuum.

In the drawing is illustrated an apparatus for uninterruptedly carrying out the boiling process.

Solutions in the preheated condition and in quantities corresponding to the progress of the boiling process are supplied into the apparatus by way of the feed-pipe 1 and 2. The regulation and supply of the liquid in the proper proportion can be carried out in any convenient manner. Three funnels 3, 4 and 5 for starting and carrying out the boiling process are arranged in the apparatus, while the funnels 6 and 7, which are provided with separate obstructions, are utilized for pre-cooling the mother lye together with the fulminating mercury already precipitated. A further cooling takes place in the water-cooled discharge funnel 8, which also is provided with obstructions. Finally the mother lye with the fulminating mercury leaves the apparatus by way of the discharge pipe 9. The funnels are mounted in a cylindric casing 10 provided with a lid 11 10@ and a bottom 9. The cylindric casing 10 guides upwardly the cooling air and the developed vapours. The latter are drawn out of the apparatus by way of a pipe 12 and are precipitated in a condenser (tubular coil or other arrangement). The valves 13 serve for shutting the funnels and regulating the liquid-level when starting the operation of the apparatus. A pipe 14 establishes communication between the interior of the apparatus and the outside air and prevents a vacuum within the apparatus as well as admits additional cooling-air blown against the distributor 15 into the apparatus. The latter is constructed of materials suited to the prevailing conditions.

The apparatus operates in the following manner:

Alcohol and mercury dissolved in nitric acid are supplied into the apparatus by way of the feed pipes 1 and 2 respectively and pass into the tunnel 3, the outlet of which is closed by the valve 13. After a short time, reaction commencesin said funnel 3. If the latter is practically filled,

the valve 13 is opened and the contents of the funnel 3 slowly ows into the second funnel 4, the outlet of which is closed by its valve 13. The primary liquids are supplied uninterruptedly. If the second funnel 4 is practically filled, its valve is opened and the liquid passes into the third funnel 5 wherein the above procedure is repeated.

From the funnel 5 the liquid with the crystals formed therein flows into the funnels 6 and 7 providedwith obstructions 16, and finally the mother lye with the crystals leaves the apparatus by Way of the last funnel 8. This funnel has a cooling jacket through which cold water circulates,A entering through pipe 18 and leaving through pipe 14.

The valves 13 remain open during the continuous operationv and the same quantity leaves the funnels as is/supplied by way of the pipes 1 and 2.

Thus the process is a quite uniterruptedprocess.

The advantages of the uninterrupted progress of the boiling process of producing fulminating mercury are:- y

1. Very high eiiiciency in View rupted boiling.

, 2. Absolutely tight closure of the apparatus during the process, and therefore, impossibility of theescape of poisonous vapours, so that the service is not dangerous.

ofthe uninter- 3. Very small costs of the plant and apparatus.

4. Impossibility of accidents by inadvertent handling.

5. Small costs of service and keeping in order the plant.

6. No transport of the apparatus within the plant and therefore great security of service.

7..,Considerable reduction of the costs of producing fulminating mercury.

The following example shows the superiority of the uninterrupted boiling process against the interrupted process.

'An apparatus for uninterrupted operation of a diameter of say 300 millimetres and a height *of4V say 2 metres yields approximately 30 kilograms in 8 hours. In an apparatus for interrupted operation for the same output are required about 1'2 boiling flasks, and it is quite evident thata large plant, a great number of workmen and so forth are necessary for this purpose.

I claimrn 1. A continuous process for the production of fulminating mercury, which consists in causing the primary liquid comprising equivalent quantities of alcohol and solution of mercury in nitric acid to 110W downwardly continuously along a common long vstepped path wherein they react on each other during the formation of fulminating mercury until exhaustion, whereby at each step of the downward flowing liquids only small quantities of fulminating mercury are present, the fulminating mercury crystals and mother liquor slowly flowing downward.

2. A process according to claim 1 in which the hot vaporsgproduced during'the formation of fulminating mercury, heat the downwardly flowing material and bring the same to an accelerated exhaustive reaction.

JOSEF MEIssNER. 

